I think this is a pretty name, either in its own right or as a nickname for Iolanthe. Now that Lola and Isla are climbing the name charts I can't understand why Iola, more refined than Lola in my opinion and prettier than Isla in my opinion, isn't also on the rise.
While it is rare today, Iola was actually somewhat common in the early 1900s and was briefly in the top 300. So the label "rare" is misleading. [noted -ed]
Iola Leroy was the main character in the novel of the same name written by Frances Harper. It is about a girl, Iola, who was briefly enslaved just before the Civil War after her father dies and it is revealed her mother is a former slave of mixed race. The novel follows her choice to live as an African American. It is one of the first novels published by an African American woman, and a very good read.